Certified Wireless USB 1.0 defines two different types of association: cable association and numeric association. In the numeric association, the CWUSB (Certified Wireless Universal Serial Bus) host and device use a specific protocol to exchange the security information. At final stage of this information exchange, both host and device need to display a number asking user's feedback. If these two numbers are the same, user acknowledge the fact by pressing “Accept” or “OK” button (or any equivalent action for confirmation). Once this is done, both host (master) and device (slave) will be able to generate the connection key as the shared secret for the following secured communication.